Seven years and one viral campaign later, Greenberg is getting a second chance.

In an announcement during Greenberg’s interview with Matt Lauer on TODAY Thursday, Miami Marlins president David Samson revealed that the Marlins will sign Greenberg to a one-day contract. The 31-year-old outfielder will face off against the New York Mets on Oct. 2. It was a Marlins pitcher, Valerio De Los Santos, who hit Greenberg with a pitch just below his right ear under his batting helmet when Greenberg was a 24-year-old rookie.

“I can’t address and express how much it means to me and all the people that are around (me),’’ Greenberg told Samson. “This isn’t just about me or an at-bat. You don’t have to do this. The Marlins organization (and) baseball in general doesn’t owe me anything, so from the bottom of my heart, I’ll be ready for it, that I can assure you.’’

“We saw this story, and we remember very well being there in 2005,’’ Samson said. “I went to Jeffrey Loria, the owner of the team and said, ‘This is someone we believe deserves to have one at-bat.’’’

Greenberg’s second at-bat is the culmination of the viral “One At Bat’’ campaign by a Cubs fan named Matt Liston, who joined Greenberg on TODAY Thursday. Liston created a website, a petition and an online trailer to garner support for Greenberg to one day get another major-league at-bat.

TODAY

Adam Greenberg points to the spot behind his ear where he was hit by a pitch in his first major-league at-bat.

Liston was watching the fateful game in 2005 and later became inspired during a screening of “Field of Dreams’’ with his wife. She was moved by the story of Moonlight Graham, the character who regretted quitting after only one big-league game.

Liston, a documentarian, started a website called the "One At Bat" campaign and a Change.org petition that received 20,000 signatures. Greenberg had bounced around three other big-league organizations but was never called up again. Currently, he is trying to make Team Israel for the 2013 World Baseball Classic, but he is not currently on a minor-league or independent-league roster.

“A lot of boys grow up dreaming of playing Major League Baseball, but I wasn’t good enough,’’ Liston said. “Here’s Adam, he gets up to the plate, he’s this close to having his dream fulfilled, and it’s taken from him in an instant, and that has always been burned in my brain. When I first started this, I was given probably a one percent chance of making this happen, but that wasn’t going to stop us because once I met this guy…I saw how hard he’s working and the elite shape he’s in.’’

The plate appearance with the Marlins will let Greenberg shed the unfortunate distinction of being the only player in Major League Baseball history to end his career on the first pitch of his first at-bat. He was the first position player since 1955 to get struck by a ball in his first major league plate appearance.

“It was the single most happiest and greatest moment of my life and the absolute worst thing at the exact same time,’’ he told NBC News.

He suffered a concussion, vertigo and blurred vision after being hit by the pitch. But Greenberg told Lauer he has no fear of getting back in the major-league batter’s box.

“After (the hit) happened the first time, I had to put it out of my mind as this is a once-in-a-lifetime, obviously, situation,’’ Greenberg said. “ I got back in the box 21 days later and said, ‘You know what, it’s never going to happen again.’’’

Samson had some words of warning for Greenberg's big at-bat next month.

“I can assure you they’re going to try to get him out, maybe on the first pitch even,’’ Samson said. “You’re going to have a chance to swing, and you better swing, Adam.”